@Mark green It
really was
not cheap, so that is absolutely not the case! He wasn't just some random office worker mate who piped up offering tiling, we know him as a professional. We also only supplied the tiles and the suite because we had been looking for exactly what we wanted for weeks before the job started and had found them already. He supplied everything else.
As I've stated a few times (I realise this thread has got quite long and many probably can't be bothered to re-read all of it) we did have other quotes beforehand for comparison. We only used him because he was available for the week we needed before the baby arrived, and having been an acquaintance meant we put some trust in him (poor judgement made in haste due to imminent baby, in hindsight).